CAMPBELL, Calif.—Ande Zerasion's voice chokes up reliving the sound of his daughter pleading for help: "Baba, I am in Sinai. Please call me."

It was early October, recalls Mr. Zerasion, a 35-year-old refugee from the tiny African country of Eritrea who emigrated here five years ago but had been forced to leave his family behind. Escaping the country with her uncle, his 14-year-old daughter, Samhar, had tried to follow a similar path to freedom. But the two had vanished in August and kidnappers had contacted Mr. Zerasion's brother in Tel Aviv, demanding $80,000 for their lives.

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It was the kind of money Mr. Zerasion, a nursing home attendant and widower in this San Jose suburb, didn't have. It was also his introduction to a nightmare world of international extortion.

In this world, he knew that the smugglers, a linked network of nomadic North African tribes, had become more sophisticated and cruel with Eritrean refugees, requiring many to leave pleas on answering machines, as his daughter had. "I was scared," he says. "Many people are (held) four or five months in Sinai. We see on the Internet the bodies, no food, no medication. They die."

To the outside world, Eritrea is a little-known sliver of Red Sea coastline above the Horn of Africa. But refugees fleeing its single-party regime have become the primary victims of what human rights groups say is one the world's more elusive and terrifying kidnapping rings. The refugees are typically captured as they cross Eritrea's border, then trafficked into regions of Egypt's Sinai peninsula that are virtually lawless, creating an open season for smugglers who hold victims while extorting family members in Africa, Europe and the U.S.

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'Many people are [held] four or five months in Sinai. We see on the Internet the bodies, no food, no medication. They die,' said Ande Zerasion, whose daughter was kidnapped after fleeing Eritrea.
Jason Henry for The Wall Street Journal

Just how many Eritreans have been kidnapped isn't known, in part because the global nature of the extortion has limited the ability of any law enforcement authority to track it. But according to a joint study by the Physicians for Human Rights and the Hotline for Migrant Workers, two Israeli nonprofits that run clinics treating victims, an estimated 5,000 to 7,000 Eritrean refugees who arrived in that country in the past three years had been tortured. Another 4,000 Eritreans have disappeared and many are presumed dead, according to testimony for the European Union.

Victims recount long periods of captivity in desert compounds where, after being forced to conduct phone-a-thons for their lives, they endure beatings, rape and grisly forms of torture.

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Samhar Zerasion, Ande's 14-year-old daughter, prays in a church in Cairo, where she now lives after being held captive for more than three months.
Ed Giles for The Wall Street Journal

The problem is "heartbreaking, especially as it has escaped the world's attention and scrutiny," said Eric Schwartz, who until 2011 was U. S. Assistant Secretary of State for Population, Refugees and Migration. Now the dean of the University of Minnesota's Humphrey School of Public Affairs, he said he has worked on human rights issues for more than 25 years. "But I have rarely if ever heard about abuses as dreadful as those perpetrated against migrants by these smugglers."

With few official accounts on the kidnappings emerging, The Wall Street Journal spent more than a year tracking down victims and families who have migrated as far away as Sweden and Texas, as well as visiting neighborhoods in Tel Aviv and Cairo where survivors congregate. Some victims, told to give out cellphone numbers by their captors, were interviewed while they were being held.

At the heart of the kidnapping is Eritrea itself, a country that has generated a steady exodus since separating from Ethiopia two decades ago. Run by the same regime since its independence, the country has been denounced by United Nations officials for systematic repression, which refugees say includes religious persecution, frequent use of the death penalty, and a military conscription program that can last for decades and amount to forced labor. A 2010 State Department report accused the military of keeping troops on "indefinite" service to operate mines, beach resorts and other businesses.

The accusations have been denied by the Eritrean government. Tesfamariam Tekeste, its ambassador in Israel, dismissed them as foreign "propaganda" that has contributed to the exodus. The extended military service is a "temporary issue," he said, needed to defend Eritrea's borders.

But according to the United Nations High Commissioner for Refugees, some 250,000 Eritreans have fled the country, about half in the past 10 years, which places the country ninth in the top 10 source countries of refugees. "The country is hemorrhaging human capital," said Tricia Hepner, a specialist on the Horn of Africa at the University of Tennessee. " The scale of displacement is comparable to what you'd see in famine or civil war."

Ironically, the path to a free life for most Eritreans has been hampered for the past two years by a different freedom effort—the Arab Spring—in North Africa. Until then, Eritreans who illegally escaped the country crossed Sudan and entered Egypt, Tunisia or Libya to reach Mediterranean-based smugglers who ferry asylum-seekers to Europe. But with these traditional routes cut off by the region's turmoil, what was once a relatively safe and cheap passage is now neither.

Instead, awaiting the refugees in transit, say diplomats familiar with the region, are nomadic tribes of Rashaida, a loose confederation of centuries-old clans who can be found on both sides of the Red Sea. Experienced traffickers of goods and people, the clans typically sell the refugees to Bedouin tribes operating in the Sinai, who then seek out expatriates who have become successful immigrants in Europe and North America. Often, those relatives have rarely seen or barely know the victims.

"They were calling me. They said they would kill him," said Woldeyesus Wube, an airline mechanic from Fairfield, Calif., with an 18-year-old nephew captured two years ago while fleeing Eritrea. Ultimately, he said, the nephew was released after he paid them $15,000. "I heard the crying. He said he was being beaten."

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"They were calling me. They said they would kill him," said Woldeyesus Wube, an airline mechanic from Fairfield, Calif., with an 18-year-old nephew captured two years ago while fleeing Eritrea. Ultimately, he said, the nephew was released after he paid $15,000.
Joel Millman/The Wall Street Journal

Victims whose family and friends are unable to raise the ransom are often never heard from again and presumed dead. According to one Egyptian human rights group, about 100 bodies of refugees who perished in the desert were sent to the central morgue in the Sinai city of El-Arish last year. Almost all were Eritreans, and human rights workers say that count may be a fraction of the total killed. Websites following the kidnappings frequently display photos of mutilated bodies found in shallow graves.

Those who have survived their kidnappings describe in similar detail an ordeal of being trafficked from one clan to another, before being deposited inside a compound. There, the captives are forced to use their kidnappers' cellphones to try to spread the word of how they can be reached, in a macabre form of marketing that has gone viral among various Eritreans communities across the globe.

"The kidnappers encourage this, they want the phone numbers in circulation," said Meron Estefanos, an Eritrean human rights activist based in Stockholm. Through a radio program she produces, she has been reconnecting captives with their families, but laments that the smugglers' tactics have led to skyrocketing ransom fees. Clans that asked for $2,000 to $3,000 a person several years ago are demanding now as much as $40,000, according to families who have been making payments.

Using one of the cell numbers, a Journal reporter last year contacted one victim, who identified herself as Semhar Malke Tesfay, an 18-year-old Eritrean, as she was being held. Ms. Tesfay said she was "traded" no less than eight times among different clans before arriving six months earlier at a Sinai camp, with eight other captives. One of them, she said, was later shot and another beaten to death. Each was regularly tortured to create background sound effects during cell calls; among the most grisly forms involved pouring melted plastics from bags onto victims' backs. "When your family says they don't have the money, it's just more plastic bags, more torture, the worst that you can possibly imagine," said Ms. Tesfay.

The daughter of a soldier, she said she was captured while heading to Sudan to find work to help support her mother and sister. In an effort to save her, she said, her family had sold their cows to come up with a $10,000 ransom. Details of her release aren't known, and she was not available for comment later, but Israeli authorities reported she arrived in Israel in June.

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Haben Akeza Mehari, who is now living in Israel, said he was saved only after his family in the U.S. came up with $33,000.
Joel Millman/The Wall Street Journal

Another captive, Haben Akeza Mehari, who is now living in Israel, said he was saved only after his family in the U.S. came up with $33,000. Weeks after his release, on a rainy night in Tel Aviv, he described months of torture in 2011—displaying a pinkish gash where clumps of hair had been torn from his scalp.

"I see one man killed by electric shock," the 20-year-old recalled, explaining that Arab guards with AK-47 rifles kept watch over dingy basement cells where he and six other men sat, usually in the dark. He doesn't know where he was being held in the Sinai, he said, because he was moved several times blindfolded. He also described a standard threat many hostages say they endure: the promise to take organs from anyone whose family doesn't raise their ransoms.

To some degree, diplomats say, the free rein Bedouins have in the Sinai is linked to a long legacy of instability in a critical part of the Middle East. After Israel signed its 1979 Camp David treaty with Egypt, both sides agreed to demilitarize parts of the Sinai. Egyptian officials say they have tried to boost security—including this past summer—but security experts say they simply cannot mount a serious challenge against smugglers capable of arming themselves so well from high ransoms.

With the army absorbed with mainland Egypt, "the Sinai is way down on its list of priorities," says Ehud Yaari, a Jerusalem-based analyst for Washington Institute for Near East Policy, a conservative think tank that reports on Israeli security issues. "The Bedouins are free to pursue their smuggling and trafficking activities unhindered,"

For its part, the international law enforcement community has started to stir—although mostly in the realm of diplomacy. Eritrean exiles in Scandinavia lobbied their new countries' officials to pressure Egypt's authorities to go after the Sinai traffickers. That led to one European Union parliament member, Sweden's Olle Schmidt, to lobby for a EU special delegation to go to the Sinai. But the envoy's report was not hopeful, saying that without reform of Egypt's security sector, "it is unlikely that situation will improve."

Washington has barely fared better. Over the past two years, the U.S. State Department has directed only a portion of a relatively small, $1 million budget item for aid to the Horn of Africa to support "community teams" that monitor refugee camps in the region where Eritreans can be preyed upon. No U.S. funding has been targeted to address law enforcement in the Sinai, said Catherine Wiesner, Deputy Assistant Secretary of State for Population, Refugees and Migration, "but various programs are under discussion with the new government."

With some 36,000 Eritrean refugees now in Israel, law enforcement authorities there have tried to act too, recently opening 10 cases of smugglers receiving ransom within Israel's borders. Six cases have led to indictments, with court proceedings pending. According to police officials in the country, a relative handful of suspects had managed to net close to $500,000 in ransom in just a few months.

Still, authorities say they doubt they can do more than scratch the surface. "The crimes are committed mostly outside of Israel," said Rahel Gershuni, who until recently was Israel's National Anti-Trafficking Coordinator.

That leaves a growing number of Eritrean immigrants who are on the receiving end of an aggressive extortion campaign with few options. Nearly 35,000 Eritreans live in the U.S., according to census data, and many have been here long enough to find jobs and buy homes, making them tempting targets. Some have tried to band together to raise money and to negotiate packaged rates to release several hostages at once.

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Amanuel Beyin, a college professor in Evansville, Ind., says he had scrimped and saved to put himself through graduate school before landing a teaching position. But after arriving on campus, with his wife and 5-year-old daughter in tow, he learned he was expected to raise $25,000—immediately—to rescue a 17-year-old cousin he had never met.
Joel Millman/The Wall Street Journal

In most cases, though, the extortion is creating one financial hardship after another. Amanuel Beyin, a 35-year-old college professor in Evansville, Ind., says he had scrimped and saved to put himself through graduate school before landing a teaching position. But after arriving on campus, with his wife and 5-year-old daughter in tow, he learned he was expected to raise $25,000—immediately—to rescue a 17-year-old cousin he had never met. "I didn't even have one 10th of that amount," said Mr. Beyin, who raised the ransom money after pooling funds from more than a dozen relatives.

Back in California, Mr. Zerasion said he told local police about the ransom on his daughter and brother, and was referred to the Federal Bureau of Investigation, where he said he filled out a form but didn't hear back for months. "They told me there is nothing they can do," he said. "Of course, I am angry." A spokeswoman for the FBI's San Francisco office declined to comment on his case.

Left on his own, and frantic, he said he reached out to the local Eritrean Orthodox Church, but that fellow parishioners could only raise about $400. Using his life savings and loans from friends—and taking a second job—he managed to raise the ransom, however, in time to get Samhar released. She is currently in Cairo, living with an Eritrean family with plans to try to emigrate here.

News of his brother was more mixed. He was released—but Mr. Zerasion says his captors dropped him off somewhere near El Arish, where he was jailed anew and his deportation process started. Yakob Zerasion was deported from Egypt to Ethiopia last week. "This is like a second jail to him," said his brother in California. "I have to do something."

—Matt Bradley in Cairo and Joshua Mitnick in Tel Aviv contributed to this article.

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